In the medical field, a biochemistry analyzer or an immunity analyzer is often used to test and analyze body fluids gathered from organisms. Commonly used test flows are shown in FIG. 1 and FIG. 2: (1) providing a clean and empty reaction vessel; (2) adding a first reagent R1 to the reaction vessel; (3) adding a sample S to the reaction vessel; (4) stirring the reaction solutions in the reaction vessel, which is also referred to as sample stirring. In FIG. 1 only a sample is added, while in FIG. 2 a second reagent still needs to be added, so that the following steps should be further performed: (5) adding a second reagent R2 to the reaction vessel; (6) stirring the reaction solutions in the reaction vessel, which is also referred to as second reagent stirring; and (7) finishing the reaction.
To react to its fullest, the reaction solutions generally need to be stirred homogeneously after reaction solutions with different compositions are added. In this regard, according to different purposes of the stirring or different reaction solutions added before the stirring, stirring during a general test may be divided into sample stirring and second reagent stirring; for some biochemistry analyzers or immunity analyzers, a first reagent stirring operation would also be performed after the first reagent is added.
In the currently known biochemistry analyzers or immunity analyzers, the stirring system and its operating way generally fall within the following cases.
In the first case, the stirring system is configured to include a plurality of independent subsystems based on different types of stirring, each subsystem comprising a drive and a stirrer. This case is subjected to the disadvantages of high cost and low reliability resulting from use of too many components.
In the second case, a single drive and a single stirrer are used to meet different stirring requirements. This case is typically subjected to such factors as low test speed, complicated cross contamination and the like. Therefore, they are generally employed in low-end analyzers.
In the third case, a single stirring system provided with a number of stirrers is used to meet different stirring requirements. Nevertheless, it is known that analyzers operating in this way at present are all subjected to the following defect that two or more types of stirring for different purposes are forcibly performed simultaneously. As shown in FIG. 3, this case allows only two states: (1) two stirrers perform stirring in the reaction vessel at the same time; and (2) two stirrers perform cleaning in the cleaning pool at the same time. Although saving time for stirring, this stirring mode may give birth to additional problems. That is, some tests do not need stirring at a certain moment while other associated tests do need the stirring. A dilemma exists in which case if stirring is not performed for the tests that require stirring, it will prevent the reaction solutions from being mixed uniformly and affect the normal operation of the reaction, thereby resulting in inaccurate test results; on the other hand, stirring performed for the tests that require no stirring will increase the risk of cross contamination, and is likely to cause changes in the absorbance of the reaction solutions, thereby resulting in inaccurate final test results.